The growth of commercial hog production facilities has led to significant political and public resistance to their operation mainly as a result of hog waste concerns. Specifically, as hog production capacity has risen over the past years, so has the volume of hog sewage that must be safely contained and treated. Current waste control methods do not always adequately manage the waste, resulting in operations which are unsanitary, smelly, and costly to operate.
Current methods of handling hog waste by many producers typically involve the use of hog waste lagoons, which is simply a hollowed open area into which the material is pumped to allow settling of the solid matter to the bottom of the lagoon and dispersal of the liquid and gas content by evaporation. Raw hog waste, which is comprised generally of a solid component and a liquid component, is pumped into these lagoons and confined, allowing solar evaporation to slowly remove the volatile liquid component of the waste slurry. However, over time, the pathogen laden solids contained in the waste slurry begin to break down and liquefy, producing a large volume of pathogen rich liquid which constitutes an environmental hazard that is costly to treat. It is common practice to periodically remove the resulting liquefied solids from the lagoon and to spray or discharge the same on agricultural fields. Obviously, as the liquefied solids retain significant bacteria or other pathogens then the spraying or discharge of such onto agricultural land poses a serious health and safety risk to the public. The continuous evaporation of the liquid acts to discharge into the air noxious gases which leads to environmental pollution which is becoming politically unacceptable. The toxic leachates and their associated volatile organic compounds as well as offensive inorganic gases and vapors emanating from such lagoons are a major source of atmospheric pollution.
The lagoon can also leak so as to cause contamination of the ground water. The discharging of such waste into the ecological environment such as rivers, tributaries, and streams, pose immediate threats to drinking water, wildlife, vegetation and food sources.